This application is a continuation under 35 U.S.C. xc2xa7120 of International Patent Application Serial No. PCT/EP01/00360, filed Jan. 12, 2001, which claims foreign priority benefits under 35 U.S.C. xc2xa7119(a)-(d) or 35 U.S.C. xc2xa7365(b) of German application number DE10001076.8, filed Jan. 13, 2000.
1. Field of the Invention
The present invention relates to, in general, panel elements, and, in particular, panel elements for forming floor coverings.
2. Related Art
Known from G9 2,256,023 A is a generic panel element. It is provided for in the floor covering formed of several such panel elements that the individual panel elements feature a certain mobility relative to each other. This enables, especially when the panel elements are made of wood and the wood xe2x80x9cworksxe2x80x9d due to exposure to the weather or due to the influence of moisture, any opening up of joints between adjoining panel elements to be avoided since the clearance possible between adjoining panel elements is designed to accommodate such movements of the natural material wood.
In some applications and depending on the furnishing style it may, however, be desirable to restrict the mobility of adjoining floor panel elements in preventing dirt from gaining access to the gaps that may materialize between adjoining panel elements. This is why it is known to fabricate non-generic floor coverings in which the tongue and groove geometries provided therein do not already prevent parting of adjoining floor panel elements. These elements first can be simply jointed, namely married and not fixedly connected until glued and safeguarded against the cited parting forces so that neither moisture nor dirt is able to gain access at the joints of two adjoining panel elements.
It is known in the field of the generic panel elements from WO 96/27719 to configure a groove from two adjoining edges of an elongated panel element, i.e. a side and an end, and to provide the lower cheek of the groove as a protruding element including a channel for receiving a complementary interlocking element at the opposite side in each case. The complementary interlocking element is configured to a certain extent at the underside of a tongue for inserting into the groove. As cited in this document these interlocking contours are configured the same on all four edges, and laying is done in rows. This means that the juxtaposed panel elements of one row to be laid first need to be connected to each other at their ends before then being married by their sides to the sides of the panels already laid. Such a procedure is, however, relatively laborious and a nuisance since several panel elements interlocked by their ends need to be handled.
Known from DE 297 10 175 U1 is a floor covering consisting of hard floor panels. The panels are provided at their sides and ends with interlocking contours. In this arrangement a panel to be newly laid is insertable into already laid panels by a swivel movement or by a horizontal shifting movement. Common to the various solutions shown is that they comprise, in the region of retaining rib and retaining groove, a bevelled contact surface area that enables a panel to turn about the butt joint at the face surface with relatively little effort and become released from the adjoining panel, resulting in gaps materializing.
Known from EP 0 855 482 B1 and EP 0 877 130 B1 is a method of laying floor panels or a floor in which one of the panels comprises an interlocking strip protruding at the underside relative to the edge by a protruding interlocking element. The interlocking profile complementary thereto comprises an interlocking groove into which the interlocking element can latch. In this arrangement no positional definition materializes since to ensure subsequent shiftability in the direction of the sides a clearance needs to be provided between the interlocking element and the interlocking groove.
Known from the DE 298 03 708 U1 is a panel for joining to an adjoining panel comprising a complementary interlocking profile but which cannot be interlocked.
Known from WO 98/58142 are panel-like components comprising on their sides a groove on one side, and a tongue on the other. The groove is configured substantially tapered so that a correspondingly configured tongue can be inserted therein. Configured at the underside of the tongue is a protuberance, and at the lower definition of the groove there is provided a recess. The protuberance is able to latch into place in the recess such that adjoining panels are safeguarded from being parted.
In conclusion, a system is known from DE 195 03 948 A1 comprising floor panels and separate retaining elements featuring rounded interlocking contours. Due to the necessity of separate retaining elements this system is complicated to lay.
One aspect of the invention is to directed to providing a panel element for forming a floor covering permitting a simple glueless laying of the floor covering while achieving and reliably maintaining a snug contact in joining adjacent panel elements.
One embodiment of the invention provides panel elements for configuring a floor covering comprising several interconnectable panel elements of the same type. The panel elements comprise a groove formed by an upper cheek and a lower cheek, and a tongue. The tongue cooperates with the groove of an adjoining same-type panel element such that two panel elements, when married, are safeguarded against parting forces acting in both axes oriented perpendicular to the side of the two panel elements. The tongue comprises, at an underside, a rib oriented in a longitudinal direction of the tongue; the groove comprises, at an underside, a retaining channel for receiving the rib of an adjoining panel element. The upper groove cheek of the groove is ramped upwards to a mouth of the groove so as to create an insertion channel for the tongue of a second panel element located at an angle to a laying plane.
In an aspect of the invention, the groove and tongue of the two panel elements, when married, comprise four defined contact locations. A first contact location is configured at an upper side of the tongue and at the upper groove cheek of the groove. A second contact location is configured at the underside of the tongue and at the lower groove cheek of the groove. A third contact location is configured at an upper sidewall of the retaining channel. A fourth contact location is configured at a rounded transition between the retaining channel and the side edge of the panel element at an angle to the third contact location.